What was done Using data from eighteen 2000-year-long proxy temperature series from all around the world that were not developed from tree-ring data (which provide significant interpretive challenges), the author (1) smoothed the data in each series with a 30-year running mean, (2) converted the results thereby obtained to anomalies by subtracting the mean of each series from each member of that series, and then (3) derived the final mean temperature anomaly history defined by the eighteen data sets by a simple averaging of the individual anomaly series, a procedure that he rightfully emphasizes is "transparent and simple."

What was learned The results obtained by this procedure are depicted in the figure below, where it can be seen, in the words of its creator, that "the mean series shows the Medieval Warm Period (MWP) and Little Ice Age (LIA) quite clearly, with the MWP being approximately 0.3°C warmer than 20th century values."

Mean relative temperature history of the globe. Adapted from Loehle (2007).

What it means Loehle notes that "the 1995-year reconstruction shown here does not match the famous hockey stick shape," which clearly suggests that one of them is a poorer, and the other a better, representation of the truth. Because of its simplicity and transparency, as well as a host of other reasons described in detail by Loehle -- plus what we have learned since initiating our Medieval Warm Period Record-of-the Week feature -- it is our belief that Loehle's curve is by far the superior of the two in terms of the degree to which it likely approximates the truth.

Judging by your style of discourse lately, I would guess that you would post an image of your middle finger accompanied by a rhetorical question.

That's not my style - sorry that you think it is. I still don't know what you meant by the rehabilitation process of the temperature record, and to respond to that I need you to explain a little more what you meant.

My hockey stick response was to show that there are now several different reconstructions available. Loehle's is another and different one. It should be pretty clear that the "answer" lies somewhere within the envelope defined by those reconstructions, and the range of possibilities gets larger the further back in time the analysis attempts to go.

So, was the hockey stick bad science? No, but the authors could have been a little more circumspect and respectful regarding inquiries.

Was it something more insidious? Certainly not.

And here's a rhetorical question: were a lot of the critiques of the hockey stick motivated by something other than concerns about its scientific accuracy?

That surface temperature data graph shows the 1940 temperature peak years to be about as warm as the 1980’s and 1990’s. That is incorrect data. You have heard that NASA corrected their temperature data and any relevant temperature graph needs to show the 1940 temperature peak to contain some of the hottest years recorded. As to why the temp chart is so incorrect, perhaps it is not factoring in ocean temps ?

I still don't know what you meant by the rehabilitation process of the temperature record.

I mean the IPCC showed a global temperature chart that looked like a hockey stick and this alarming chart was printed in the major media to boost support for the Kyoto treaty. Do you really think this was not bad science? I say it was political science used to advance a political agenda.

Now that the original study has been exposed, we see new, (more credible?) charts to sell the same idea. At some point somebody has to question the veracity of the people who have promoted one lie, got caught, and are now trying to sell another lie.

Before we go any further, are you really of the opinion that the current global temperature is actually .3 degrees warmer than it was at the peak of the Medieval Warm Period as indicated by the graph you posted?

Before we go any further, are you really of the opinion that the current global temperature is actually .3 degrees warmer than it was at the peak of the Medieval Warm Period as indicated by the graph you posted?

Put it this way; if you add the warming since 1992 to the end point of the Loehle plot, that's about what you get as well. So is there any data that DOESN'T indicate that? (Remember that it's warmed up globally about 0.4 C since 1975. That's a big spike. I'd have to say that the early 1990s were about as warm as the peak MWP -- maybe -- because I'm still not sure about the weighting effect in North America and Europe, where it was most strongly expressed.)

I mean the IPCC showed a global temperature chart that looked like a hockey stick and this alarming chart was printed in the major media to boost support for the Kyoto treaty. Do you really think this was not bad science?

The IPCC process is about evaluating scientific results for the edification of decision-makers. It is not science itself. Therefore, what you describe above is not bad science. Bad science is about poor methodology, erroneous result interpretation, letting a desired conclusion determine the methods of analysis (and many other "bad" practices). We could talk a lot about that; I prefer it to the mixture of policy and science that frequently colors this discussion.

"A continued mode of corrections using approaches where statistical uncertainties are not quantified is not a scientifically sound methodology and should be avoided, considering the importance of such surface station data to a broad variety of climate applications as well as climate variability and change studies."

"In general, the adjustments indeed correct a large portion of nonclimatic biases in these poorly sited stations as far as the difference between the NARR/NNR and station data is concerned."

Long paper, I skimmed it. Seems like his final conclusion is that to have a better sense of the uncertainty of the temperature measurements, it would be good to have better station records and better-sited stations. Well, gee... it's hard to argue with that. It doesn't, however, invalidate the temperature trends derived from the station data.

Something went wrong with the source links to the original images in the article. I recommend reading my original article. If you don't want to read everything in the comments, the post I recommend you examine is #69.

Since you didnt answer my last comment, I had thought you were done with this thread, now I find you have been busy pulling links from all over to discount secondary arguments or comments here.

According to a review of the thread, this was your last comment:

It will be interesting if research continues to find some variable that accounts for the oscillations and resolves some of the contentions that seem to be driven by political expediency.

My reply would have been, and is now: "Yeah, it would be interesting." As far as I know, there are lots of oscillations: PDO, AO, AMO, ENSO -- off the top of my head. Multiple oscillating cycles produce some pretty interesting waves, don't they?

What, exactly, is your interest in all this?

Keeping the science straight. The thread touted the Loehle paper as "Because of its simplicity and transparency, as well as a host of other reasons described in detail by Loehle -- plus what we have learned since initiating our Medieval Warm Period Record-of-the Week feature -- it is our belief that Loehle's curve is by far the superior of the two in terms of the degree to which it likely approximates the truth." (This is from CO2Science, a notably biased skeptical source.) So I examined Loehle, examined the correction paper, determined that the correction paper's conclusions aren't nearly so stunning (but this still interesting and is respectable research), and discuss this.

We seem to be able to measure an increase in temps around the world at much greater resolution than before but there also seems to be a growing need to assign blame rather than isolate cause.

Weill, if you identify the cause, then you can easily blame the process identified as the cause, can't you? It IS important for science to identify/isolate the causes of climate change to correctly attribute anthropogenic forcing vs. natural forcing. Once that's done, the anthropoids should be blamed appropriately.

How would you characterize your personal position?

Vertical, fortunately. ;-) But I'm actually not sure what position you're asking me to characterize.

So is there any data that DOESN'T indicate that? (Remember that it's warmed up globally about 0.4 C since 1975.

You know, temperature excursions of that magnitude have happened several times in recorded history. Going by this chart, from 1879 to 1912 there was drop of 0.6 degrees C. If we had today's politicians back then they would be calling for a stranglehold on the economy to prevent another ice age. From 1944 to 1956 there was another drop of 0.4 degrees. Or what about that huge increase of .7 degrees from 1912 to 1944, long before most of our CO2 was released? If back in 1912 or 1944 you had glued the recorded temperature record on to a 2000 year chart of proxy data you would have a very scary looking picture.

Temperature spikes happen. But ancient records don't show it because they don't have the one year temporal resolution that we have in recorded history. So it doesn't really mean much to talk about spikes if you don't have anything to compare it with.

Bad science is about poor methodology, erroneous result interpretation, letting a desired conclusion determine the methods of analysis (and many other "bad" practices). We could talk a lot about that; I prefer it to the mixture of policy and science that frequently colors this discussion.

Unfortunately we can't separate the mixture because government scientists who do environmental studies are being influenced and their careers threatened by political forces. So we can't avoid talking about it.

By the way, I neglected to answer your question about the possibility that objections to the Hockey Stick were motivated by other considerations. Yes. Absolutely. I think it was motivated by concern about grand theft Kyoto. Mega-theft. It it were about mating practices of bugs, no one would care. But the Hockey Stick affect was bad science being used by world politicians in a continued, unabashed attempt to grab money and control.

Rural temperatures actually had a more rapid warming trend, according to this study.

Actually, rural areas that became more urbanized would, as you would expect, have a greater increase in temperature than big cities that are not laying down any new asphalt. More urbanization, more heat island effect, more warming. Of course he had to pose it as a refutation of urban heating. Don't these people get dizzy when they spin like that?

OK, point 1. You get that 0.6 C drop using annual numbers, not the 5-year means, and 1877-1878 was a period with a big El Nino. (*See note.) The 5-year mean curve drops about 0.2 C. Not so for 1975-present.

* The temperature minimum corresponds to the years just after 1883. Can you think of anything notable that could have had a climate effect in 1883?

Or what about that huge increase of .7 degrees from 1912 to 1944, long before most of our CO2 was released?

Well, to make you happy, that's been attributed to CO2 + increasing solar activity, the Sun given responsibility for 30-50% of it. I estimate the five-year mean increase at about ~0.5 C, by the way.

Unfortunately we can't separate the mixture because government scientists who do environmental studies are being influenced and their careers threatened by political forces.

The studies can still be critically analyzed, no matter who wrote them.

By the way, I neglected to answer your question about the possibility that objections to the Hockey Stick were motivated by other considerations. Yes. Absolutely. I think it was motivated by concern about grand theft Kyoto.

It's good that you know that. My problem is that attacks purporting to be scientific, but which were not and which would clearly be labeled "bad science", were launched at the Hockey Stick, seriously confusing the issue. Some of the erroneous points made about it eight years ago are still being restated today. Yes, the original Hockey Stick has methodological flaws. But when you look at all the reconstructions in the figure I offered -- from ClimateAudit, created by a colleague of Loehle -- the basic hockey stick picture is still there, with only the amplitude of variability and the phasing (somewhat) being the main things that change.

I could say a lot more. But I still want to stay focused on the science. What we need to know scientifically is how much natural variability is contributing to the current temperature rise. On that topic paleoclimate reconstructions can aid assessment, but they are not the full answer by a long shot. So to compare peak MWP temperatures to now and conclude that because they were about the same we currently don't have a problem is not a conclusion backed by a preponderance of scientific data.

Yes. The point I was making was that the amplitude of the temperature peaks depend on the filtering of high frequency signals by either running averages or, in the case of data before the historical record, by averaging inherent in the proxy technique. Does anyone really know how much?

But when you look at all the reconstructions in the figure I offered -- from ClimateAudit, created by a colleague of Loehle -- the basic hockey stick picture is still there

How much of this reconstruction relies on tree-ring data?

What we need to know scientifically is how much natural variability is contributing to the current temperature rise.

Before we do that we should first determine how much of the temperature rise is real or caused by: a) Local artifacts like Heat Island Effect b) Improper siting of temperature stations c) Errors from aging instruments d) Mathematical errors or outright fraud

Good science allows transparency so that other scientists can see your data and your methods. Unfortunately that is difficult with much of government science and getting harder all the time. Data sets have been moved to pay-per-view sites or given only grudgingly. NCDC weather site data has been withdrawn entirely citing "privacy" concerns. The formula and algorithms used by computer models are shielded from public scrutiny. This is not good science. This is a medieval priesthood.

Yes. The point I was making was that the amplitude of the temperature peaks depend on the filtering of high frequency signals by either running averages or, in the case of data before the historical record, by averaging inherent in the proxy technique. Does anyone really know how much?

I am completely not an expert, but I can intuitively state that it is probably not good practice to evaluate trends based on maximum-to-minimum points when the data has considerable variability. Filtering is useful, but I can't say much more about it.

Can't tell from the graph. Certainly some does. Ask McIntyre! But we're discussing Loehle, which is a tree-ring-free analysis -- and the same basic picture emerges. Most of the question is about the global significance of the MWP temperatures.

Yes, it's always good to evaluate the quality of the data. I've been following the discussions of data quality, and I believe this: if you had "perfect" data, you'd see maybe a 10-25% difference in the trends observed now. Here's a couple of things to think about when you are considering data quality:

The reason I provide these -- and I could provide others -- is that these "natural" indicators demonstrate clearly that a temperature increase is happening, regardless of cause. What would be confounding would be to have all these natural indicators, yet the instrumental data did not show an increasing trend.

A lot of people are going to die from this little weather spike before it is all over. If China were bound by Kyoto can you imagine how they would cope with cold weather like this if they could no longer heat their homes with fossil fuels but were restricted to wind and solar power.

Cold kills more people than warmer weather. If the Earth cools off it is going to be much worse than a heating trend .

Yes, I agree, my phraseology was unfortunate. A 0.4 C rise in 30 years is not a spike. (It isn't based on a valley-to-peak maximum difference, either.)

I was thinking about those links you posted (BTW what do they have to do with "data quality?) trying to support global warming theory with anecdotes, when I saw this today,

What I posted is not anecdotal. Each of the articles is about an observation of a trend. A spring thaw a month early is an anecdote, as is one bitterly cold winter. A trend of spring thaws a week earlier over a century is a shift of significance BECAUSE it shows a change in one direction of a highly variable occurrence. The tropopause height is a clear indicator of the state of the GLOBAL climate -- it essentially synthesizes everything occurring above and below and reacts.

The reason that this is about data quality is that the natural trends are in the same direction as would be indicated by the data. This means that though it may be necessary to keep refining the error bars on the direct instrumental observations, the data and the trends provide mutual support. Everything "fits".

I was originally responding to this comment:

Before we do that we should first determine how much of the temperature rise is real or caused by: (list of instrumental problems)

In essence I was saying that most of the temperature rise has to be real, or otherwise we would not be seeing the significant shifts in natural indicators.

BTW, the correct term for this is "phenologic". A couple of years back there was a big paper about this. Let me look...

Got it. "Ecological responses to recent climate change", 2002. Google Scholar indicates it has been cited 853 times. That's impressive. What I'm still looking for is a free copy...

Re. your post about sea, lake and river ice. Ice freezes and thaws in cycles. This can be a win-win for you if you want to sell the notion of a warming trend. If we have a cold period with a lot of ice buildup you can talk about record amounts of ice melting when it starts to warm up again. But if we have a warm period where much of the ice has melted, then you can talk about record low ice extents even if we start to head for a cold period. Of course I’ll do just the reverse. Isn’t this fun?

Another thing about ice is that it is supposed to create a positive feedback. Ice melts, lowering albedo and causes more melting. But Antarctic ice extents are at a thirty year high in spite of the warming over that period. Could it be that there is also a negative feedback with ice? Sea surface warms, evaporating water that becomes ice in Antarctica, increasing albedo which lowers temperature.

This can be a win-win for you if you want to sell the notion of a warming trend.

Well, yes I do. And the data indicate a warming trend over the past 150 years, no matter how much you try to confuse the issue and avoid the question.

The data in the paper: later freeze, earlier thaw. Consistent with global warming. No other additional conflations.

Why do you suppose no one has updated this data series? It seems like it would be an easy thing to do.

Well, two things. The data set is highly variable. 12 more years might not add much information to it. Two: did you look at the first link, the authors, and the date? It's a short article; read the whole thing.

Another thing about ice is that it is supposed to create a positive feedback. Ice melts, lowering albedo and causes more melting. But Antarctic ice extents are at a thirty year high in spite of the warming over that period. Could it be that there is also a negative feedback with ice? Sea surface warms, evaporating water that becomes ice in Antarctica, increasing albedo which lowers temperature.

Did I previously provide the link to the paper by a physicist at U. Washington that shows that increasing Antarctic sea ice is a consequence of global warming. Aw, h*ll, this is so much fun I'll do it again. Don't ask me to support this one with analysis; all I can do is take his word for it.

Estimates of sea ice extent based on satellite observations show an increasing Antarctic sea ice cover from 1979 to 2004 even though in situ observations show a prevailing warming trend in both the atmosphere and the ocean. This riddle is explored here using a global multicategory thickness and enthalpy distribution sea ice model coupled to an ocean model. Forced by the NCEPÂNCAR reanalysis data, the model simulates an increase of 0.20 Ã 1012 m3 yr−1 (1.0% yr−1) in total Antarctic sea ice volume and 0.084 Ã 1012 m2 yr−1 (0.6% yr−1) in sea ice extent from 1979 to 2004 when the satellite observations show an increase of 0.027 Ã 1012 m2 yr−1 (0.2% yr−1) in sea ice extent during the same period. The model shows that an increase in surface air temperature and downward longwave radiation results in an increase in the upper-ocean temperature and a decrease in sea ice growth, leading to a decrease in salt rejection from ice, in the upper-ocean salinity, and in the upper-ocean density. The reduced salt rejection and upper-ocean density and the enhanced thermohaline stratification tend to suppress convective overturning, leading to a decrease in the upward ocean heat transport and the ocean heat flux available to melt sea ice. The ice melting from ocean heat flux decreases faster than the ice growth does in the weakly stratified Southern Ocean, leading to an increase in the net ice production and hence an increase in ice mass.This mechanism is the main reason why the Antarctic sea ice has increased in spite of warming conditions both above and below during the period 1979Â2004 and the extended period 1948Â2004.

Have you noticed that we are getting farther away from the human-caused aspect of the warming trend that is supported (well within past ranges before man’s influence) with each of the denier’s statements.

It is admitted that it isn’t necessary to prove that the current and recent past is warming slightly; what is important to the skeptic is that this is the time for caution, not panic and overreaction.

Rising sea levels over a time frame that outran adaptation by the coastal dwellers could prove to be costly, but so far that isn’t the case.

Sea levels can only rise by melting of trapped land ice or thermal expansion of the sea itself (unless the ground is sinking).

The only loss of ice we have charted remains largely seasonal and has been limited to the northern hemisphere.

While the northern hemispere is much more important to the majority of living creatures it is not the whole globe.

Trying to remove the present carbon-load in the earth’s air would prove to be far more costly and disruptive to industry that any gradual rise in sea levels.

If it were accepted that mankind caused it, we still would have to remember that it took hundreds of years for it to be noticed and get to its current state.

What makes anyone think that we can stop and then reverse the process overnight or even a few generations?

128
posted on 02/06/2008 11:49:46 AM PST
by Old Professer
(The critic writes with rapier pen, dips it twice, and writes again.)

If there was no instrumental data at all, just the observations of the trends in the paper, what would be the logical conclusion regarding the direction of change for global climate?

I don't believe anyone can draw any conclusion from that study. I have less respect for ecologists than I do for climate scientists. At least climate scientists make an attempt to prove their theories using scientific methods. An ecosystem is complex and chaotic. There is no proof that warming is causing all the changes he talks about. They can advance a theory and rationalize it but there is no proof. Species change radically for dozens of reasons even when the temperature doesn't change.

Months ago there were people saying that polar bear populations were at risk from global warming. The ice was melting and the bears were drowning. Trouble was, most types of polar bears were increasing in number.

Living things have a lot more to worry about than a slight increase in temperature.

shows that increasing Antarctic sea ice is a consequence of global warming

So we used to believe that a runaway positive polar feedback effect was waiting to bite us in the butt and now we discover that the science is not settled. We used to believe that the Sun was a constant, and now we know that it is a huge variable in climate change.

Every few years we are discovering new things that radically alters the picture of things that change the climate. In view of this, maybe we should wait until the science settles down before pressing the panic button.

Well, yes I do. And the data indicate a warming trend over the past 150 years, no matter how much you try to confuse the issue and avoid the question.

Maybe for the last 27 years. Steve McIntyre was reviewing the heat island effect and the data paint an interesting picture of the differences between rural and urban stations. There was a cooling period 27 years ago but the trend shows a fairly level trend for 117 years if you leave out the really big cities.

Every day I wake up I tell myself not to be surprised when what I expect to happen happens, but I keep hoping anyway.

I have less respect for ecologists than I do for climate scientists. At least climate scientists make an attempt to prove their theories using scientific methods.

That's a completely unfair characterization of the science of "ecology", which covers a lot of ground. Much of this comes under the heading of population biology, ornithology, botany, zoology -- do you have problems with those sciences, too?

There is no proof that warming is causing all the changes he talks about.

Wondrous, this emphasis on "proof". Science is about supporting hypothesis/theory with observations and data. In this case, the theory is that warming climate would cause a variety of shifts in a certain direction of many different phenological indicators. Examining the indicators, more than 90% show a shift in the predicted direction. That's solid support.

Months ago there were people saying that polar bear populations were at risk from global warming.

Interesting that I'm pursuing this on another thread. They are at risk. Care to know why? Their main food source is seals. Seals swim in the ocean, and they occasionally get out on the ice to rest. Polar bears hunt seals from sea ice, floating on the ocean. With less sea ice, there are less seals on the ice, and the polar bears have less area to hunt from (polar bears are real good at waiting at seal breathing holes and grabbing them when they come up for air). The data show that when sea ice diminishes significantly, polar bear weights go down and polar bear populations decline.

Drowning polar bears is an anecdote. The above statement is polar bear ecology.

Living things have a lot more to worry about than a slight increase in temperature.

In the figure below, Ive calculated the average unadjusted temperature for actual cities,

First question that pops into my head reading this is: is there a reason that the "unadjusted" temperatures are preferable to the "adjusted" temperatures? Reading the article, my first impression is that the unadjusted temperatures are preferable to McIntyre because he can find trends in them and then cast aspersions on the adjustments because they remove the trends -- when maybe the reason for the adjustments (left unstated) is to remove spurious trends.

You can try all you want, but nature and the data indicate that it warmed up in the 20th century and its warming up faster now -- globally. You can't "adjust" when a lake thaws in the spring.

...maybe the reason for the adjustments (left unstated) is to remove spurious trends.

One of the spurious trends I've noticed is the practice of climate scientists to cherry-pick data. It's pretty obvious that Peterson choose a very peculiar selection of cities for his heat-island study.

I'll wait for an audit of Magnuson's choice of lakes and rivers before I'll buy it as real.

In this case, the theory is that warming climate would cause a variety of shifts in a certain direction of many different phenological indicators. Examining the indicators, more than 90% show a shift in the predicted direction. That's solid support.

Yeah, but does the theory come before or after the data is collected? I suspect that, in many cases, the theory is proposed after the fact.

I'll wait for an audit of Magnuson's choice of lakes and rivers before I'll buy it as real.

In the interests of your health, I advise you not to hold your breath. Realize that the 2000 study was supported by the 2005 Great Lakes study, both of which I've cited to you. And Magnuson's data is all online. Let McIntyre edit all he wants. It may interest to you to know that the general process of scientific peer-review actually discovered a small error that reduced the reported trends by about a day. I'll leave it to you as an exercise to find out what the error was.

The paper was an analysis of many different types of phenological studies. If you had read it -- I suggested that was something you could try -- you probably could have answered your question. Essentially, the paper says: "Observations indicate a warming climate in most parts of the world. Observations indicate that organisms are recently exhibiting changing behavioral and distributional patterns. Most of the observations of the organisms indicate that the changes the expected adaptations to a warming regime. There are very few observations that don't show such an expected response."

Most of the observations of the organisms indicate that the changes the expected adaptations to a warming regime

And all of these expectations were published where before the studies were actually done? And don't tell me to go look it up myself. You people are trying to sell the world on a huge bill of goods. The burden of proof is on you.

And all of these expectations were published where before the studies were actually done?

That's such a weird question I don't know how to answer it. Look, here's an example. Posit a warming climate. Prediction: flowering trees will bloom earlier in a warming climate. Go check the studies. Voila! 9 out of 10 studies of flowering tree bloom timing show earlier blooming. The change is in the expected direction in a warming scenario.

Now, I don't know if I can find an explicitly published prediction that such observations would be made; I expect that I could with unlimited resources and time. I have neither. Instead, review the following to help augment your understanding.

Now, I don't know if I can find an explicitly published prediction that such observations would be made

I doubt if you could. Ecosystems are so complex that there are an infinite number of rationalizations that you could make to attribute warming to the observed changes.

Hell, you could even make predictions in advance just like Jeane Dixon did. With enough people making enough predictions some of them will eventually hit pay dirt. You have plenty of media support to broadcast the winners and ignore the losers.

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